Grinding gauge caliper frame



July 22, 1941.

H. H. LEWIS GRINDING GAUGE CALIPER FRAME Filed May 15, 1940 2 Sheets-Sheet 1 INVENTOR ATTORNEYS July 22, 1941. H. H. LEWIS GRINDING GAUGE CALIPER FRAME Filed May 13, 1940 2 Sheets-Sheet 2 ATTORNEYS Patented July 22, 1941 UNITED STATES PATENT OFFICE GRINDING GAUGE CALIPER FRAME Howard H. Lewis, Peoria, 111.

Application May 13, 1940, Serial No. 334,912

7 Claims.

My invention relates to new and useful improvements in calipering devices.

An important object of my invention is to provide a calipering device that includes means for mounting the same on a grinding machine and wherein the association of the device with the machine is unique to permit the same to be used with great speed and precision.

Another object of my invention is to provide a device of the above-mentioned character which is uniquely constructed to permit the caliper to be introduced into a cylindrical groove in the Work and that permits calipering of relatively small work sections of the type found in certain constructions of crankshafts, and the like.

Still another object of my invention is'to provide a device of the above-mentioned character which includes, as a constituent part of the caliper assembly, scale means for obtaining a rough setting of the work being measured, and indicator means for accurately and precisely indicating the exact amount of stock removed from the Work.

Yet another object of my invention is to provide a device constructed and operating in the above-described manner that may be applied to the work during the actual grinding operation, thus giving instant and exact measurements without necessitating the stoppage of the grinding to take the measurements.

Other objects and advantages of my invention, will be apparent during the course of the following description.

In the drawings, forming a part of this specification, and wherein like numerals are employed to designate like parts throughout the same,

Figure 1 is a side elevation of a device embodying my invention,

Figure 2 is a front elevation thereof, and showing the same associated with a grinding machine,

Figure 3 is a side elevation of my device with one of the side plates of the frame removed, and showing the same associated with a grinding machine,

Figure 4 is a transverse sectional view taken on the line 44 of Figure 3,

Figure 5 is a transverse sectional View taken on the line 5-5 of Figure 3,

Figure 6 is a transverse sectional view taken on the line 6-6 of Figure 3,

Figure 7 is a transverse sectional View taken on the line I -4 of Figure 3,

Figure 8 is a transverse sectional view taken On the line 88 of Figure 7, and

Figure 9 is a transverse sectional view taken on the line 9-9 of Figure 8.

In the accompanying drawings, wherein for the purpose of illustration, is shown a preferred embodiment of my invention, the numeral l0 designates the grinding wheel of a grinding machine and the numeral ll designates a hood or shield arranged above the wheel. The work i2 is mounted in front of the wheel and is adapted to be ground thereby to a selected size in the conventional manner.

My device contemplates a calipering instrument which may be mounted on and supported from the hood H and which is used to apprise the operator when a selected amount of stock has been removed from the work l2. The caliper elements l3, l4 and I5 are cooperatively related by the frame l6, which frame comprises spaced parallel bars l1, l8 and IS the opposite sides of the bars being closed by plates 20 and 2| to define the spaced parallel open ended passages 22 and 23.

The caliper element l3 comprises an elongated bar slidably mounted within the passage 23 and limited in its movement therein by the transversely extending pin 53. The upper end 24 of the bar extends above the frame and is contacted by the plunger 25 of the amplifying gauge or indicator 26, and the lower end 21 thereof extends slightly beyond the frame and terminates in a work contacting point 28, adapted to bear against the surface of the Work l2 at a point directly above the axis thereof. The indicator 26 cooperates with the caliper element 13 to indicate the movement of the element relative to the frame, it may be of conventional type with a spring depressed plunger 25 which coacts with the caliper element l3 in a manner whereby the element i3 may be urged by the work to move the plunger against the spring, which operation will, in turn, be recorded on the dial 26 of the indicator, or it may be spring urged in theopposite direction to a limited extent to follow the work, as the conditions may require.

As clearly illustrated in Figures 1 and 3, the lower ends of the bars l8 and IQ of the frame extend substantially below the bar I! and the edges 29 of the portion of the plates extending between the bars I! and i8 are beveled at an angle of 45 relative to the longitudinal axis of the frame. The caliper element [4 is formed with a shank 30 which is snugly but slidably received within the passage 22 of the frame. The wing headed bolt 46 extends transversely through the frame and through the elongated slot 41 in the shank 3d, the extendin end 43 thereof being screw-threaded to receive the nut 49 which may be tightly threaded thereon to hold the shank immovably located within the passage 22 of the frame or which may be loosened thereon to permit free sliding movement of the shank longitudinally within the passage. The plate 34 is provided with an elongated slot 50 which opens into the passage 22 and against the shank 30. The pointer 5| secured to the shank by the bolt 5! is reciprocally actuated by movement of the shank within limits defined by the slot to eiiect a reading on the vertical column of figures 52, stamped or otherwise impressed in the plate laterally of the slot. The portion of the caliper element is extending below the beveled edges 2- of the frame includes an upwardly directed tongue 3! which slidably engages the outer edge of the bar ll to assure proper alignment of the shank within the passage 22, and a portion of the extending end of the element M extends below the work l2, the inner edge 32 thereof being arcuately cut away to accommodate the 01k the distal end thereof is provided with a contact point 33 which is adapted to engage the surface of the work :2 at the side thereof diametrically opposed to the point 28.

The third caliper element i5 comprises companion plates 3:! and 35 mounted on the opposite sides of the portion of the caliper element l4 extending below the frame. The central portions of the plates are connected by a shim 38 slidably received within the elongated slot 31 in the element M. The plates and shim are held in proper association with each other by the rivet 38 whi h holds the inner surfaces of the plates in snug but slidable engagement with the opposite sides of the inter osed element M. The portions of the plates above the rivet 38 are provided with inwar ly extending registering bosses 2E and d which extend through the arcuate slot and the screw 32 extends through the bosses and holds the pla es snugly pressed but in sliding engagement with the opposite sides of the element id. The slot 31 is parallel with the longitudinal axis of the frame and the slot 4! is arcuately curved and angularly arranged relative thereto in a manner to hold the upper ends 43 of the plates in engagement with the beveled edges 23 of the plates 23 and 2i and the lower ends as of the plates 34 and 35 are provided with a work engaging point 45.

The indicator is adjustably mounted on the frame in a manner to permit ne same to be shifted toward or away from the frame, whereby any desired reading may be obtained on the dial 534. The split annulus 55, formed on the upper end of the bar i5, is arranged laterally of the frame and the tubular shank portion -8 of the dial is slidably fitted to the stem 57 extending upwardly from the annulus 55. The coil spring 58 is seated within the tubular shank 55 and acts to normally urge the same upwardly relative to the stem. An adjusting screw 59 extends through the upper end of the shank 56, through the coil spring 58 and into screw-threaded engagement with a bore which opens through the upper end of the stem.

The work engaging points 28 and 33 of the caliper elements and M are arranged in diametrically opposed relation to the work (2 and the point 5 of the third caliper element i5 is arranged circumferentially intermediate the opposed contacts. The ends 53 of the centering caliper element 2' 5 are at all times maintained in engagement with the beveled edges 23 of the frame and the relation of the centering element with the diametrically opposed elements [3 and i4 is such that engagement of the point 45 with the periphery of the work will locate the points 28 and 33 at diametrically opposed sides of the work.

If the work being measured is, for example, a two inch shaft and it is desired to remove .010 stock therefrom, the pointer 5| is moved to a position opposite the numeral 2.000 in the column of figures 52. Movement of the pointer to the above position will move the work contacting point 33 of the caliper element it away from the diametrically opposed work contacting point 28 of the caliper element E3. The pin 53 will normally permit the spring pressed plunger 25 of the indicator 2% to urge the caliper element l3 a maximum distance away therefrom. When the pointer 5! is set opposite the numeral 2.000, the distance between the work contacting points 28 and 33 is equal to or slightly less than two inches. The column of figures 52, therefore, provides a means for roughly setting the instrument to the diameter of the work. When the upper ends of the intermediate centering calipering element l5 are moved into en agement with the angular edges 29 of the frame and the three caliper points fitted to the work, the points 28 and 33 will be automatically positioned at diametrically opposed sides of the work by the point 45 and the point 23 of the calipering element l3 will ride along the surface of the work to raise the said elem nt and to cause the same to indicate a reading on the dial 54 of the indicator.

If it is desired to remove .010 stock from the work, the adjusting screw 59 may be rotated to obtain a 10 reading on the dial 54 of the indicator. If, for instance, the indicator hand is rotated in an anti-clockwise direction as far as the numeral 20 on the dial when the inctrume: is applied to the work, the adjusting screw 59 may be raised slightly to permit the spring pressed plunger 25 to move downwardly and to permit the indicator hand to move in a clockwise direction as far as the numeral 10. The reading obtained on the dial indicates the amount of stock to be removed from the work I 2.

The instrument is supported from the grinding wheel hood H by means of the swinging arm 6|, the inner end of the arm being provided with a split annulus 62 which is fixedly clamped to the end 53 of the spindle 64 by the threaded bolt 65. The spindle is snugly, but rotatably, received by the collar 65 cf the bracket 61 mounted on the hood of the grinding wheel and the end 68 of the spindle extends substantially beyond the collar 66. The coil spring E0 is carried by the extending end of the spindle and has the end '10 thereof imbcdded in the shank while the end 1| thereof is received within a registering recess in the face of the collar 52; as best illustrated in Figure 7. The resilient action of the spring tends to rotate the spindle 64 in a clockwise direction and to swing the arm 61 upwardly. The outer end of the arm is formed with a collar 12 which receives the end 13 of the spindle M and the set screw 75 extends through the collar and into engagement with the spindle to hold the same against rotation therein. The bushing 76 is snugly, but rotatably, tted to the other end of the spindle 14, and the split annulus portion 55 extending rearwardly from the frame is fixedly clamped to the bushing by the set screw ll. The end 18 of the bushing extends laterally of the split annulus 55 and the extending portion is formed within an external annular groove 10, which groove loosely receives the jaw 8'0 of the locking collar 8|. The set screw 82 is carried by the collar 8| and with the inner end thereof in pressed engagement with the spindle 14 to prevent movement of the collar axially of the shank. The relatively loose engagement of the jaw portion 80 within the groove 15 of the bushing will prevent movement of the caliper frame axially along the spindle 14 and consequently will prevent the movement of the caliper points 28, 33 and 45 axially along the work 12. The operator may, however, pivotally move the instrument to the dotted line position of Figure 3 by virtue of the fact that the bushing 16 is in no wise prevented from rotating freely on the spindle 14.

When the caliper points 28, 33 and 45 have been applied to the work in the manner hereinbefore described and the selected reading has been obtained on the dial 54 of the indicator, the points may be disengaged from the work and the work may be rotated and caused to engage the grinding edge of the wheel H1. The removal of the contact points from the work will permit the spring 69 to automatically swing the arm BI upwardly to position the calipering instrument in a readily accessible but unobstructive position.

When it is desired to again calibrate the work, it will not be necessary to stop the work in order to apply the instrument thereto. The operator may grasp the arm 6| to lower the instrument and by pivoting the lower end thereof in the direction of the work, the contact points may again be fitted to the work. The inter mediate calipering element l5 will assure the proper centering of the three points and the tendency of the spring 69 to urge the arm 6! upwardly will hold the point 33 in pressed engagement with the periphery of the work. The limited movement of the bar I3 will permit the same to ride along a portion of the work surface and to be elevated slightly in a manner to cause a movement of the indicator dial in an anticlockwise direction. If the indicator hand, on the second application of the instrument to the work, is moved to 5 on the dial, the operator knows that he has removed approximately onehalf the necessary stock from the work. The grinding of the work is continued until the indicator hand registers on the dial 54. A 0 reading on the dial appraises the operator of the fact that he has removed .010 stock from the work.

Figure 1 clearly indicates that the instrument may be set for varying sizes of work shafts. If a larger piece of work, indicated by the dotted circle 83, is substituted for the work l2, the nut 49 is loosened to permit the caliper element l4 to be lowered relative to the frame. If the circle 83 designates a three inch shaft, the pointer is moved to a position opposite the numeral 3.000 on the column 52 to appraise the operator that the points 28 and 33 are properly set to accommodate a three inch shaft. The bevel of the edge 29 of the frame will cause the end 43 of the intermediate caliper element to move therealong and the contact point 45 thereof to move radially outwardly a distance equal to one-half the distance traveled by the lower contact point 33, thereby relocating the three contact points at the opposite and mid-points of a. new and larger circle. The indicator 26 may again be adjusted in accordance with the amount of stock which it is desired to remove from the instant work.

The frame and caliper elements are uniquely corelated to produce an essentially thin structure which may be readily introduced into a cylindrical groove in the work or which will permit accurate calipering of relatively small shaft sections, such as the section 84 of the crankshaft 85 illustrated in Figures 1, 2 and 3 of the drawings. The device may be expeditiously used with speed and precision and by using the pointer 5|, it will not be necessary to employ any other instrument to obtain a proper initial setting; All of the means necessary to obtain a proper setting of the instrument are incorporated in the structure herewith shown and described. The column of figures 52 permits the diametrically opposed points 28 and 33 to be rapidly set for any particular work and the amplifying gauge 26 may be rapidly and accurately adjusted to permit an extremely accurate reading to be obtained. When the instrument is not in use, the coil spring 69 will hold the same in an elevated and unobstructive position and, when it is desired to use the same, it will be positioned within easy reach of the operator.

It is to be understood that the form of my invention, herewith shown and described, is to be taken as a preferred example of the same, and that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of my invention, or scope of the appended claims. I

Having thus described my invention, I claim:

1. A caliper instrument comprising a frame having diametrically opposed movable caliper elements, means to adjustably position one of the caliper elements and to hold the said element in the adjusted position, an indicator adapted to show movements of the other of the caliper elements, and a third caliper element adjustably mounted on the first caliper element and having a part normally contacting an edge of the frame, the relationship between the edge of the frame and the third caliper element being such that movement of the first caliper element relative to the frame and adjustment of the third caliper element on the first element to move the said part into engagement with the edge of the frame will position the work contacting end of the third element on the periphery of a circle inscribed through the work contacting ends of the said diametrically opposed elements.

2. A caliper instrument comprising a frame having diametrically opposed movable caliper elements, and a third caliper element adjustably mounted on the first caliper element, said lastmentioned caliper element having a part adapted to contact an edge of the frame, the relationship between the edge of the frame and the third caliper element being such that movement of the first caliper element relative to the frame and adjustment of the third caliper element on the first element to move the said part into engagement with the edge of the frame will position the Work contacting end of the third element on the periphery of a circle inscribed through the Work contacting ends of the said diametrically opposed elements.

3. A caliper instrument having three circumferentially spaced caliper elements, two of said elements being diametrically opposed and the intermediate element being adjustably mounted on one of the diametrically opposed elements and arranged circumferentialiy intermediate the opposed elements, and means relating the three elements having provision for the radial adjustment of both of the diametrically opposed caliper elements and for automatically causing radial movement of the intermediate element through a distance equal to one-half the distance traveled the element on which it is mounted.

4. A caliper instrument having three circumferentially spaced caliper elements, two of said elements being diametrically opposed, one of the diametrically opposed elements being permitted a limited radial movement the other of the diametrically opposed elements being permitted a relatively great radial movement and the intermediate element being adjustably mounted on the last-mentioned diametrically opposed el ment and arranged circumferentially intermediate the opposed elements, and a support relating the three elements, said support having provision for selective radial adjustment of the lastmentioned diametrically opposed element and for causing automatic radial movement of the intermediate element carried thereby through a distance equal to one-half the distance traveled by the mentioned diametrically opposed element, and an indicator adjustably mounted on the support and associated with the limitedly movable caliper element for recording radial movements thereof.

5. A caliper instrument having three circumferentially spaced caliper elements, two of said elements being diametrically opposed, one of the diametrically opposed elements being permitted a limited radial movement the other of the diametrically opposed elements being permitted a relatively great radial movement and the intermediate element being adjustably mounted on the last-mentioned diametrically opposed element and arranged circumferentially intermediate the opposed elements, and a support relating the three elements, said support having provision for selective radial adjustment of the last mentioned diametrically opposed element and for causing automatic radial movement of the intermediate element carried thereby through a distance equal to one-half the distance traveled by the mentioned diametrically opposed element, scale means carried by the support and cooperative with the last-mentioned diametrically opposed caliper element to indicate the selected position thereof, and an indicator adjustably mounted on the support and associated with the limitedly movable caliper element for recording radial movements thereof.

6. A caliper instrument comprising a frame provided with spaced parallel passages, a caliper element having an essentially limited sliding movement in one of the passages, a caliper element having a relatively great sliding movement in the other of the passages, said last-mentioned element having a work contacting point arranged in diametrically opposed relation to the work contacting point of he said first element, a third caliper element aojustably mounted on the lastmentioned caliper element having a part adapted to normally contact an edge of the frame, the relationship between the edge of the frame and the third caliper element being such that movement of the second caliper element relative to the frame and adjustment of the third caliper element on the second element to move the said part into engagement with the edge of the frame will position the work contacting end of the third element on the periphery of a circle inscribed through the Work contacting points of the said diametrically opposed events, a supporting arm for the frame, spring means urging the arm upwardly to hold the points of the caliper elements in engagement with the work.

'7. A. call provided with spaced parallel passages, a caliper lement having an essentially limited sliding movement in one of the passages, a caliper element having a relatively great sliding movement in the other of the passages, said last-mentioned element having a work contacting point arranged in diametrically opposed relation to the work contacting point of the said first element, a third caliper element adjustably mounted on the lastnicntioned caliper element having a part adapted to contact an edge of the frame, the relationship between the edge of the frame and the third caliper element being such that movement of the second caliper element relative to the frame and adjustment of the third caliper element on the second element to move the said part into engagement with the edge of the frame will position the work contacting end of the third element on the periphery of a circle inscribed through the Work contacting points of the said diametrically opposed elements, an indicator associated with the limitedly movable caliper element for recording movements thereof relative to the frame, said indicator being adjustably mounted on the frame and relative to the said caliper element to permit a selected initial reading to be obtained equal to the stock to be removed from the work, movement of the limitedly movable element to effect a zero reading on the indicator apprising the operator that the requisite amount of stock has been removed from the work.

HOWARD H. LEWIS. 

